I have a friend who rides a rigid cross bike on single tracks, he loves chasing down $5,000 full suspension bikes, especially the riders who tell him this or that trail is too dangerous for a single speed single rear rim brake cross bike.
I've seen him do it,, come off a black diamond trail that's a few miles long still on the back wheel of the fast guys on the dream bikes...
Funny,,His bike, he built for,,,,$700
His reason,, said he was too competitive, would wind up In the hospital,, His bike keeps him In check..